Okay well I'll add to your argument.
Here is a picture of Temari smiling.
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Here is a picture of Minato smiling.
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What do these two have in common? Well they both have nice blonde hair and beautiful smiles. Both of them are quite intelligent as well, so could it be that Minato also has the same element as Temari, therefore he has wind release just like her?

Just something to think about.
Now to add something serious. Killer Bee's tentacles have very little durability feats so it isn't too impressive cutting them. If Minato had actually used wind release to power up his kunai at that point in time, he should have been able to slice through it completely with ease. Not saying he doesn't have wind release since I do believe it is likely for him to do so but your whole argument of cutting most of the tentacle isn't that great of a feat to make me believe he does have it.